The present invention relates to paperboard containers for liquids and blanks therefor and more particularly to aseptic containers for liquids having a pouring spout formed therein and an associated implement to open the pouring spout and withdraw the liquid contents of the container.
The term "aseptic" as used in the specification and claims herein in connection with a container or package is intended to include a gas- and liquid-tight container that is free of pathogenic organisms.
A search of the prior art failed to uncover any prior art references which disclose the aseptic container or blank of the present invention. A number of patents were uncovered which disclose liquid containers and blanks of varying design and complexity. The following is a list of the U.S. patents uncovered during the aforementioned search: U.S. Pat. Nos. 1,161,759; 3,981,430; 2,926,832; 4,101,051; 3,520,464; 4,171,064; 3,770,185; 4,244,474; 3,795,359; 4,294,362.
U.S. Pat. Nos. 3,795,359; 4,171,064; and 4,294,362 disclose parallelepipedic aseptic liquid containers or blanks therefor having a sealed seam along the top surface which is initially formed in a gable-top configuration and then folded down to form a substantially flat top surface. The containers disclosed in U.S. Pat. Nos. 3,795,359 and 4,294,362 are formed of a tough paperboard-foil-plastic laminate and are provided with tear lines in or across the sealed top seam of the containers which are intended to be torn or cut to provide a pouring spout. However, since the tear lines are provided in the double-wall thickness top seam adjacent the fused sealing line, it is frequently difficult to effect a tear of the tough laminate material, especially if the tear lines are not properly formed or aligned or if there is insufficient material to grasp to effect the tear of the seam. It is also sometimes necessary to use a scissors or other cutting implement to open the container.
U.S. Pat. Nos. 1,161,759 and 3,623,632 disclose paperboard containers for which drinking straws or pouring taps are utilized for withdrawing or pouring the contents from the containers.
The remaining patents listed above disclose other types of pouring spouts or tear strip openings of varying design and complexity for paperboard containers. However, the pouring spouts and tear strip openings for the containers disclosed in those patents are not particularly suitable for use with the paperboard laminate of conventional aseptic containers. Moreover, such spouts and openings are typically located in an exposed portion of the container and are thus subject to tampering.